Swing grinder



April 14, 1931.

F. W. MARSCHKE ET AL SW1 NG GRlNDER Filed Nov. 18. 1925 2 Shreets-Sheel` 1 April 14, 1931.` F. w. MARscHKE ETAL v1,800,307

` SWING GRINDER Filed Nov. 18, 1925 2 SheetS-Shee*` 2 Ag TORNEY.

i an twisting of belts.

Patented Apr. i4, i931' Um'rsn STATES PATENT OFFICE f :mman w. msm! um menons 'ro wml, A NBPOMTION ()IIv UDMA IANUIACTUBUG will, 0l' Mmmm SWING Gmnappunti meaimvember is, im. semi n. n.rl.

with our invention and h from the ceil- It is the object of our invention make a high-du swing grinder which is readily A and eas' y adaptable to different characters of work, and is simile and easy to operate with a minimum of atigue for the operator; vto make such a swing grinder adJustable to vdierent angles, with a maintenance of balance in all adjustments; and to provide a simple drive for the grinding wheel without ca out our invention, we mount the grinding wheel on one end of a leverframe, which carries at its other end the motor and is supported at an inter- .15 mediate point so that the weight of the motor substantially counterbalances the weight of the grinding wheel; though we desirably provide a connterweiglit for getting the balance more accurately and to compensate for 2o variations in the weight of the grinding wheel, as from wear and replacement. The motor is drivingly interconnected to the driving wheel by a driving connection, preferably a belt; and is maintained with its axis in fixed angular relation to the axis of the grinding wheel, so that such driving connection may not if it is a belt. The lever-frame which carries both the grinding wheel and 3o the motor is adjustable to various angular positions about its own axis, to tilt the plane of the grinding ace. The support by which the lever-frame is carried at its intermediate point includes a suitable bearing for ame about its own axis, and a mounting for such bearing to permit it to have both a universal angular movement and a reciprocating movement, so that the operator at the grinding wheel may swing the wheel to and fro along the general line of the axis of the lever-frame, may raise and lower the grinding Wheel as desired, and may swing the grinding wheel from side to side an even around in a complete circle when he so desires, and may do all this without twisting the driving belt.

The accompanying drawings illustrate our invention: Fig. 1 is a perspective side view lof a swing grinder constructed in accordance of the be interfered with, as by P psrmitting this adjustment of the lever.

d shelf 2O may be separate pieces,

ing; Fig, 2 is also a perspective view of such swing "nder, slightly idler-frame, and with only a part of the support shown; Fig. 3 is a transverse section through the lever-frame near the supporting bearing thereof; Fig. 4 is a vertical central section through the ceiling turn-- table shown in Fig 1; Fig. 5 is a front view of the swing grinder shown in Fig. 1; Fig.. 6 is a side elevation of a swing grinder embodying our invention but supported from the iloor below instead of from the ceiling above; and Fig. 7 is a section on the line 7--7 of Fig. 6.

The grinding wheel 10 is mounted on a shaft 11, desirably at one end thereof, and is located between two prongs 12 and 13 at one end of a lever-frame 14. The shaft 11 is mounted in two bearings 15 carried by the prong 1,3 but spaced apart thereinto provide space between them for a driving pulley 16 which receives the driving belt 17. The driving belt 17 connects the pulley 16 to the pulley 18 on the shaft of a driving motor 19; which is carried by a shelf 20l rovided at the other end of the lever-frame 14 from that at which the grinding wheel 10 is located. The motor 19 may be of anydesired type, usually an electric motor, and controlled in any desired way, as by ushbuttons 21 at the front end of the leverame 14 governing control .mechanism located in a box 22 carried by the frame of the motor. Since such control mechanism comprises no part of the present invention, we have not attempted to show it. The motor 19 is desirably longitudinally adjustable on the shelf 20, to provide for tightening the belt.

The lever-frame 14 is conveniently made of an I-beam, laid on its side, with a reinforcing rib 25 extending along one 'of its sides; and the prongs 12. and 13 and the suitably attached, as by rivets, to the end of such I- beam.

The lever-frame 14 is supported at an intermediate'point, so that it may be turned about its own axis, may be reciprocated inl general along its own axis, and may have its tilted aboutthe axis` winnen n. nummer munt..

' surrounds axis swung both up and down and sidewise with a universal movement. To this end, a ring bearin 30, shown as a rollerbearing,

e lever-frame 14, the rollers being located between innerl and outer rin s 31 and 32; and the1 inner ring 31 is r1 gid y attached to the lever-frame 14 at an 1ntermediate point of the latter ('Fi 1 and 2) as by a single wide leg 33 which pro ects :from` the inner ring 31 against the we of the I-beam of the lever-frame 14 and is attached thereto by bolts 34. The outerring 32 is suitabl supported to give the reciproeating and tbe universal angular movements above referred to, by mechanisms which will be described later. The rin bearing 30- 31-32 provides for turning t e lever-frame about its own axis to any desired position, as is clear from Figs. 1 and 2, with a mm1- mum of labor on the part of the operator. l

The axial ends of the ring bearing may be closed by cover-rings 35, attached to the inner ring 31. These cover-rings 35 have ears 36 which project upward over an arc-shaped slot 37 provided in an upward extension 38 of the outer ring 32; and a clamping bolt 39 passing through such slots joins the ears 36 of the two cover-rings 35 to clamp them against the extension 38 to hold the inner and outer rings 31 and 32 in any desired angular relation to each other. If desired, stop-screws 40 may be mounted. in the extension 38, to extend alon the slot 37 from the ends thereof to provi e limit-stops for the turning of the inner ring 31 relatively to the outer ring 32; so that the lever-frame 14 and the parts carried` thereby may be returned exactly to a denite position about the axis of such lever-frame after having been moved from such position for any reason. y

The location of the ring bearing 30-31- 32 on the lever-frame 14 is such that such lever-frame and the parts carried thereby constitute a unit which is in substantial balance with respect to such ring-bearing. .This balance is desirably provided both as between the two ends of the lever-frame, withl the ring bearing as a' supporting intermediate fulcrum,` and also about the axis of the lever-frame so that there is substantiall no tendency for such lever-frame to turn a out its own axis by gravity. To this end,the shelf 20 is oli'set from the plane of the leverframe 14 as a whole, to get the center of gravity of the motor and of the lever-frame substantially in the axis of the lever-frame; v

and the axis of the grinding wheel 10 desirably intersects the axis of the lever-frame. Further, to make up for wear and replacements of the grinding wheel 10, a counterweight 41 is mounted on a rod 42 extending longitudinally of the lever-frame beneath the motor end thereof, and is adjustable .longitudinally of such rod 42 to. produce the .by standing between handles 43 insertable in holes 44'in the sides .of a yoke 45 joining the ends of the prongs 12 and 13; there usually bein several such holes 44 in eachV side of the yo e 45 to permit inserting the handles 43 in different positions so that the two .handles may be in substantially the same horizontal plane 'for different tiltinoof the lever-frame and its carried parts a ut the axis of such lever-frame.

The yoke 45 may also provide a support* c etfor the front end of a long-shank so wrench 46 for operating the clamping bolt 39, the forward end of such socket-wrench being provided with an operating handle 47 in convenient proximity to standing between the handles 43.

The mounting for the outer ring 32 of the rin bearing, to provide the reciprocating an the universal angular movements above referred to, may take different forms. We have shown one such form in Figs. 1 to 4 inclusive, and another form in Fi s. 6 and 7 In the arrangement shown ingFig's. 1 to 4 inclusive, the extension 38 of the 4ring 32 has'two upwardly extending ears 50 between which is located the lower end of a lswin rod 51 connected to such ears by a pivot-pin 52 transverse to the axis of the lever-frame 14 or parallel to the axes of the rinding wheel 10 and driving motor 19. Tle upper end of the swing rod 51 vlies between two ears l53 depending from a turn-table plate 54 and is connected thereto by a pivot-pin 55 parallel to the pivot-pin 52. The two pivot-pins 52 and 55 permit the swin ng of the device as a whole in the general ine of `the axis of the lever-frame 14, to produce the [desired reciprocaftion off the grinder wheel 10 over the work being ground; and also permit the ready raising and lowering of the grinding wheel 10 as desired. The turn-table plate 54 is mounted within a ceiling-fitting 56, which has an inwardly projecting flan e 57 at the bottom to su port the edge o the turn-table plate, andp outwardly projecting iin ers 58 at the top for receiving attaching bolts by which such fitting is attached to the ceiling. This turntable mounting permits the device as a whole to be turned about the axis of such turn-table; and with the two pivot-pins 52 and 55 provides for the `universal angulai movement of the lever-frame and for the reciprocation of the lever-frame as required by the nature of the work being ground.

In the arrangement shown in Figs. 6 and 7, the ringr32 issupported from the floor in om the ceiling, but is supported stead of the operator ico . rst mentioned handles.

to have the same general movement. To this end, the ring 32 may be turned around so that its ears project downward to receive between them an upstanding su porting finger which is connected to suc vears by the pivot-pin 52 already described. The finger 60 is carried by a frame 61 supported on two pairs of Ilanged rollers 62 which v travel in two parallel runways 63 extending along opposite sides of a turn-table 64 centrally mounted on a vertical pivot-pin 65 on a supporting pedestal 66 which rests on the floor. The runways 63 are shown as rectilinear runways, to provide a rectilinear reciproca-tion; but this rectilinear feature is not necessary. Each runway has upper and lower bars, between which the flanged rollers lie. The axis of the vertical pivot-pin 65 of the turn-table 64 is desirably about at the center of the figure formed by the rollers 62. The pivot-pms 52 and 65 and the roller mounting of the rollers 62 inthe runways 63 in the arran ement shown in Figs. 6 and 7 provide the esired reciprocability of the rinding wheel along the eneral axis of the ever-frame and also for teuniversal angular movement of the lever-frame.

We claim as our invention:

1. In a swing grinder, a suspended annular bearing including outside and inside relatively rotatable-members, a pin and slot connection between said members limiting the extent of their relative rotation, a frame p extending through said bearing perpendicular to the plane of rotation thereof and supported by theinner member above the ax1s of said membera grinding wheel atone end of the frame and a motor at the other said wheel and motor bein so disposed line drawn throu h t eir centers of mass passes through said frame at its place of intersection with said bearing, said pin slot connection includin means for clamping said members in di erent relative angular positions and means for adjustably varying the length of said slot.

2. In a swing grinder, a suspended annular bearing including outside and inside relatively rotatable members, a pinand slot connection between said members limiting the extent of relative -rotation thereof, a frame extending through said bearin pernection between said membersvlimit' the extent of relative rotation thereof, a ame extending through said bearing perpendicular to the plane of rotation thereof and supported by the inner member above its axis, a grinding wheel at one en of said frame and a motor at the other, a bifurcated member ad'acent said grindin wheel, bearings carrie b the arms of sai bifurcated member in w 'ch an extension of the shaftof said grindin -wheel is journaled, a belt pulley carrie by said shaft between said bearings, a belt connection between said ulley and said motor, said bifurcated memr being offset suiliciently to cause said belt vto clear said suspended annular bearing in all positions of rotation of the latter.

In witness whereof, we have hereunto set our hands at Indianapolis, Indiana, this 14th day of November, A. D. one thousand nine hundred and twenty-five.

FREDRICI-I W. MABSCBKE. v WILLIAM A. MABSCBKE.

that a p pendicular to its plane of rotation an supl ported by the inner member, a 'grinding wheel at one end of the frame and av motor at the other, said pin and slot connection including means for clam ing said members in different relative angular positions, handles for tilting vsaid ame, and-a clamp operating handle for said pin and slot connection extending to a point adjacent said 3. In a swing grinder, a suspended annular bearing including outside and inside relatively rotatable members, a pin and slot con- 

